Center Section Leading Edges:
Pioneer Aero’s engineering team has been working hard on the leading edges for the SBD’s wing center section for some time now. As noted previously, most of this structure suffered significant impact damage when the aircraft ditched in Lake Michigan during WWII. As a result, Pioneer has had to remanufacture nearly all of these components from scratch, a task which Hadon Smith has organized.
Righthand Assembly Completed:
Smith’s team recently completed the principle structural elements for the righthand leading edge, from the nose spar forwards. They then back-drilled the forward set of inter-spar ribs and had them primer-painted, meaning that the righthand assembly is now ready for mounting onto Spar #1 (once that component is ready to receive it).
Lefthand Leading Edge Beginnings:
With the righthand side essentially done, Hadon Smith began working on the lefthand center section leading edge assembly. He first reconfigured the "Dinosaur bones” - flipping the set of profile boards from righthand to lefthand use - and aligning the jig with a laser to ensure each board was positioned properly. Smith then started rolling a tapered radius into a sheet of appropriate gauge aluminum sheet to begin fashioning the new lefthand leading edge skin. Using an English Wheel, he fettled the skin's curvature until it fitted snugly into the jig. The skin remains oversized presently but, like the righthand unit, it will have its edges trimmed during final-fitting when the assembly is ready for mounting in the wing center section.
The set of lefthand leading edge ribs, formed at the same time as the righthand set, has undergone heat treating, straightening and trimming. Once the leading edge skin is correctly profiled, Hadon will fit, primer-paint and then rivet in these ribs to begin forming the assembly.
To convert the set of profile boards (dinosaur bones) for building the lefthand center section leading edge assembly, each board was rotated 180º around its long axis and then positioned precisely using a laser (note the bright green line scanned across each “bone” in the image). This ensures that the two leading edges are both symmetrical and match drawing dimensions. (Image via Pioneer Aero Ltd.)
This is the first stage of fabricating the skin for the lefthand center section leading edge. Hadon Smith has just started pressing the tapered profile into the oversized sheet of 2024-T3. Getting this right is a time-consuming process which also demands a lot of skill from the engineer performing the task. (Image via Pioneer Aero Ltd.)
The lefthand leading edge skin sitting in its jig. The correct tapered curve is evident, with fine tuning involving the use of an English wheel. Note that the cutout for the wheel well has also been roughed in. (Image via Pioneer Aero Ltd.)
